Adjustable sliding compasses



May 5, 1970 EIJI SHIMOYAMA ADJUSTABLE SLIDING COMPASSES 3 Sheets-Sheet 5 Filed March 18. 1968 INVENTOR BY EIJI SHIMOYAMA PM d 8 ATTORNEYS United States Patent Ofice 3,509,631 ADJUSTABLE SLIDING COMPASSES Eiji Shimoyama, 2358 Nishi-magome, Ohta-ku, Tokyo, Japan Filed Mar. 18, 1968, Ser. No. 713,687 Claims priority, application Japan, Mar. 20, 1967, 42/22,845; July 1, 1967, 42/ 56,217 Int. Cl. B43i 9/04 US. Cl. 33-27 7 Claims ABSTRACT OF THE DISCLOSURE A compass is provided for describing arcs of selected radius length, comprising two separate elements adapted to be connected by a standard measuring means such as a tape measure or a straightedge. One element establishes the center of the arc to be described. The other element holds an arc-describing means, as forexam-ple a pencil, pen or knife edge. The measuring means defines the radius of the arc.

BACKGROUND OF THE INVENTION This invention relates to adjustable sliding compasses, and more particularly to a new and improved compass for describing large radius arcs.

Conventional two-leg compasses become unwieldy in drawing large radius arcs. Accordingly, strings, beam compasses, or curve rules are generally used for this purpose, but known devices are inaccurate and expensive.

SUMMARY OF THE INVENTION The purposes of the present invention are realized by an improved adjustable compass which can be operated easily and accurately and which may be manufactured inexpensively.

An aspect of the invention is its provision of an instrument for drawing arcs and for cutting arcs out of paper, cloth, and other materials.

Another aspect is its provision of an improved adjustable compass capable of convenient use with a flat measuring means of conventional type, such as a metal. straightedge or tape measure.

In accordance with the invention, a compass is provided for describing (i.e., drawing or cutting) arcs of selected radius length, including two separate elements which are adapted to be mounted on, and connected by standard measuring means, such as a tape measure or a straightedge. One element serves as a holder for a pivot pin, which establishes the point about which the arc is described. The other element comprises a drawing instrument which has a plurality of apertures for receiving arc-describing devices, as for example, a pencil, pen or knife edge. The measuring means is held within the two elements by an arrangement of slots, clamps, and springs, so as to define the radius of the arc to be described. Index lines inscribed on the elements of the compass provide reference points for each of the different arc-describing means so that by reference to an appropriate index line on the element holding the pivot pin, the length of the radius of the arc to be described may be ascertained. Radius length is adjusted by sliding the device containing the pivot pin along the measuring means to a selected position.

BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the invention may be had from a reading of the following detailed description and inspection of the drawings in which:

FIG. 1 is a top view of a sliding holder in accordance with the invention;

FIG. 2 is a side view of the sliding holder of FIG. 1;

FIG. 3 is a back view of the sliding holderof FIG. 1;

FIG. 4 is a front view of theysliding holder of FIG, 1;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 1;

FIG. 6 is a sectional view taken along line 6--6of FIG. 1;

FIG. 7 is a top view of a drawing instrument in accordance with the invention;

FIG. 8 is a side view of the drawing instrument of FIG. 7;

FIG. 9 is a front view of the drawing instrument of FIG. 7;

FIG. 10 is a back view of the drawing instrument of FIG. 7;

FIG. 11 is a bottom view of the drawing instrument of FIG. 7;

FIG. 12 is a sectional view taken along line 12.12 of FIG. 7;

FIG. 13 of FIG. 7;

FIG. 14 is a sectional view taken along line 14-14 of FIG. 7;

FIG. 15 is a perspective view of an embodiment of the invention arranged for use with a pencil and a tape measure; and,

FIG. 16 is a perspective view of an embodiment of the invention arranged for use with a knife and straightedge.

is a sectional view taken along line 1313 DETAILED DESCRIPTION OF I THE INVENTION The embodiment of the invention shown in the drawings comprises two elements, a sliding holder 14 (FIG. 1) and a drawing instrument 15 (FIG. 7) containing a first slot 21 and a second slot 22, respectively, for receiving conventional measuring means connectingxthe sliding holder 14 and the drawing instrument 15. The slots 2-1, 2-2 are arranged to receive measuring means of a conventional straightedge type. Beneath the slots 21, 2-2 are narrow channels 3-1, 3-2which are arranged to receive narrow measuring means of the conventional tape measure type. The first slot 2-1 and. its associated first narrow channel 31 in the sliding holder 14 extend longitudinally throughout the extent of the sliding holder 14 terminating in apertures at the front and back longitudinal ends as shown at the right and left, respectively, in FIG. 1. The second slot 2-2 in the drawing instrument 15 terminates in an aperture at the front of the drawing instrument 15 (shown at the left in FIG. 7) and in a first planar end surface 2-3 whose plane is perpendicular to the slot 2-2 and includes the center of an aperture 8 (FIG. 7). The second narrow channel 3-2 terminates in a front aperture and a second planar end surface 2-4 which is parallel to the plane of end surface 2-3 and spaced longitudinally from end surface 2-3. Several top apertures 8, 9 and 10 (FIG. 7) are disposed in the top surface of the drawing instrument 15 and are adapted to receive marking and cutting devices as described below. Top apertures 8, 9, 10 communicate with vertical passageways 20, 21, 22, respectively. Vertical passageways 20, 21, 22 are directed perpendicularly to second slot 2-2 and communicate, respectively, with bottom apertures=8', 9', 10' disposed in the bottom surface of the body of the drawing instrument 15.

In using the adjustable compass with a straightedge ruler, the end of the straightedge bearing the zero reference point is insertedinto the front aperture of the Patented May5, 1970 3 clamp screw 17 (FIG. 7). Thus, the'zero point end of the straightedge ruler is in the plane of the center of the aperture 8. The other end of the straightedge ruler is inserted into the front longitudinal end aperture of the first slot 2-1 (FIG. 1) in the sliding holder 14 so that a graduation line on the straightedge ruler corresponding to the desired radius length is aligned with one of several index lines -1, 5-2, 5-3 (FIG. 1) inscribed on the top surface of the sliding holder 14 depending on which of the top apertures 8, 9 or 10, respectively, is used to receive the marking or cuttingdevice. The alignment is achieved by adjusting the position of the selected graduation line until it isaligned with the selected index line. The body of the sliding holder 14 may be made of transparent material, to allow visual aligning of the measuring means with the indexlines. The straightedge ruler is fixed in place by tightening. a clamp screw 1 (FIG. 1). Springs 13 (FIG. 1) and 19 (FIG. 7) have the function of pushing the measuring means against the clamp screws 1 and 17, respectively, and of properly aligning the measuring means by urging the measuring means portions in the sliding holder 14 and the drawing instrument 15 to the same positions relative to the width of the slots 2-1 and 2-2.

In use with a conventional tape measure, the zero point end of the tape, whose case is placed on a rest space 7 at the back longitudinal end of the sliding holder 14 (FIG. 1), is threaded through the narrow channel 3-1 in the first slot 2-1 from left to right, as seen in FIG. 1. The tape is then inserted into the narrow channel 3-2 of the drawing instrument 15. The tape measure is pushed through slot 2-2 until it strikes the planar end surface 2-4. The hook of a conventional tape measure is received in an opening 11 adjacent planar end surface 24 (FIG. 7), and the tape is fixed in place by tightening the clamp screw 17. The planar end surface 24 is spaced at a distance from a plane including aperture 8 and perpendicular to slot 2-2 to accommodate the length of the hook assembly. of a conventional tape measure. Thus, the zero point of the tape islocated in the same plane as the plane in which the zero point end of the straightedge ruler was located in the example discussed above.

Top apertures 8, 9, 10 with their respective vertical passageways and bottom apertures are adapted to receive a pencil point with an adjacent tapered pencil portion, a pen point with an adjacent tapered portion and a knife edge, respectively. After the compass has been assembled in the manner described above, a pivot pin is inserted into a top aperture 4 (FIG. 1) disposed in the top surface of the sliding holder 14 and communicating with a bottom aperture 4 througha vertical passageway 23 directed perpendicularly to the first slot 2-1. The

pin is pushed through vertical passageway 22 until it.

emerges at bottom aperture 4'. If the invention is to be used with a pencil, the point portion of the pencil is inserted in the aperture 8 of the drawing instrument 15 and pushed through vertical passageway 20.11ntil it emerges at bottom aperture 8'. The pivot pin is fixed by pressure into the material in which the arc is to be inscribed, and the pencil point is pressed into contact with the materiaLthe pivot pin and pencil being adjusted so that the measuring means is substantially parallel to the plane of the material. The drawing instrument .15 is then rotated about the pivot pin. A

For cutting arcsont of substantially planar surfaces,

a knife edge is inserted through the slot 9 in the drawing instrument 15 and pushed through vertical passageway 21 until the edge emerges through bottom aperture 9.

In use with a drawing pen, the pen is inserted through the aperture 10 of the drawing instrument 15 and pushed through the vertical passageway 22 until the point emerges through bottom aperture 10'. A pared step 12 (FIG. 8) is provided to protect the working surface from any dripping ink. The pared step 12 is the form taken by the bottom surface in the area of the aperture 1 due to the presence of an extra layer of structural material in that area; The extra layer allows for the complete containment of the pen point assembly exposing only the actual point to the surface.

The center of the aperture 4 is at the same distance from the first slot 2-1 as the centers of the apertures 8, 9 and 10 are from the second slot 22. The straight edge, or other measuring means, should be so placed as to be parallel to a line drawn through the apertures 4, 8, 9 and 10. The index lines 5-1, 52, 5-3 are spaced at equal distances in the preferred embodiment; also, a set, of zero point indicating lines 6-1, 6-2, 6-3 (FIG. 7) pass through the centers of apertures 8, 9, 10, respectively, and are spaced at equal distances from one another, the distances between the index lines being equal to the distances between the zero pointindicatinglines. Therefore, the distance between lines 62 and 61, the radius of the are described by the knife edge in aperture 10, is determined by reference to the distance between 5-2 and 6-1, which can be read directly from the measuring mark of the measuring means aligned with the former line; similar considerations apply to pairs of lines 63, 5-1 and 6 1, 5-3. Thus, Zero point radius length measure is provided for each of the apertures 8, 9, 10; in case of use With a pencil, a knife or a drawing pen, radius length may be selected by reference to the reading graduation lines 5-1, 5-2, 53, respectively. For this reason, in a preferred embodiment the line pairs 61, 5-1; 5-2, 6-2; and 5-3, 6-3. are the same color, the color of every line pair differing from that of every other line pair.

A further feature of the invention is its usefulness under conditions of difiicnlt operation due to lack of space or to the curvature of the surface in which the arc is to be described. The invention provides the possibility of cutting the desired arc out of another surfaceand usingthe are as a curve rule on the surface in which the arc is to be described.

The adjustable sliding compass can be used in conjunction with substantially fiat straight edges, tape measures, and other measuring means of conventional type. Such measuring means having differing widths. The slots in the drawing instrument 15 andthe sliding holder 14 which receive such measuring means are of dimensions which will allow the passageinto them of a wide range of conventionally used measuring means.

Although a detailed, description is given above of .certain preferred embodiments in accordance with the invention by way of example, any and all modifications, improvements or alternative arrangements falling within the scope of the appended claims should be considered. to be a part of the invention. t

What I claim is:

1. A sliding compass for adjustably describing an arc of a selected radius length comprising:

a sliding holder and a drawing instrument adapted to be connected by a measuring means, said sliding holder having: 1

a body with first front and back longitudinal ends;

a first slot with a first. front aperture at said first front longitudinal end for receiving measuring means extending longitudinally along the length of said sliding holder body and terminating in a back aperture at said first back longitudinal end;

a plurality of index lines disposed on said sliding holder body and directed' substantiallyperpendicularly to the direction of the first slot;

a first aperture in said sliding holder body for receiving a pivot pin, said aperture communicating with a first vertical passageway extending in a substantially perpendicular direction to the plane of said first slot, said pivotpin aperture lying along said index line closest to a first aperture of said first slot;

first adjustable clamping means for fixing in place measuring means in said first slot;

said sliding holder body having a transparent portion for facilitating visual alignment of a measuring mark on said measuring means with a selected index line;

and said drawing instrument having a body with second front and back longitudinal ends;

a second slot with a second front aperture at said second front longitudinal end for receiving measuring means, said second slot extending longitudinally through said drawing instrument body;

a plurality of second apertures disposed along the length of the drawing instrument body, each second aperture communicating with its own second vertical passageway directed substantially perpendicularly to the plane of said second slot in said drawing instrument body, said second apertures and second vertical passageways being adapted to receive are describing means, the number of said second apertures and said index lines being equal, the spacing of said index lines and said second apertures being related in that for each of said second apertures spaced at a given interval from a second aperture nearest said second slot front aperture there is an index line equally spaced from an index line closest to said first slot front aperture;

said drawing instrument body having a transparent portion for facilitating visual alignment of a mark on said measuring means with a related second aperture.

2. A sliding compass for adjustably describing an arc of a selected radius length comprising:

a sliding holder and a drawing instrument adapted to be connected by a measuring means, said sliding holder having:

a body with first top and bottom surfaces and first front and back longitudinal ends;

a first slot with a first front aperture at said first front longitudinal end for receiving measuring means extending longitudinally along the length of said sliding holder body and terminating in a back aperture at said first back longitudinal end;

a multiplicity of index lines spaced along the top surface of said sliding holder and directed substantially perpendicularly to the direction of said first slot;

a first top aperture in said top surface for receiving a pivot pin, said top aperture communicating with a first vertical passageway extending between said top and bottom surfaces of said sliding holder, body in a substantially perpendicular direction to the plane of said first slot,

said first vertical passageway terminating in a bottom aperture, the center of said top aperture lying along said index line closest to the front aperture of said first slot;

a first adjustable clamping means for fixing in lace measuring means in said first slot;

said sliding holder body having a transparent portion for facilitating visual alignment of a measuring mark on said measuring means with a selected index line;

and said drawing instrument having a body with second top and bottom it surfaces and a second front longitudinal end;

a second slot with a second front aperture at said second front longitudinal end for receiving measuring means, said second slot extending longitudinally through said drawing instrument body and ending within said. drawing instrument body at a first planar end surface; h

a multiplicity of. second top apertures in said top surface each communicating with its own second vertical passageway directed substantially perpendicularly to the plane of said second slot and extending between said top and bottom surfaces in said drawing instrument body, each of said second vertical passageways terminating at a second bottom aperture in said bottom surface, each said second top aperture with its communicating second vertical passageway and second bottom aperture being adapted to receive are describing means, the center of said second top aperture closest to said second slot front aperture being substantially in the same plane as said planar end surface and the number of said second top apertures and said index lines being equal, the spacing of said index lines and said second top apertures being related in that for each of said second top apertures spaced at a given interval from said second top aperture nearest said second slot front aperture there is an index line equally spaced from said index line closest to said first slot front aperture;

a second adjustable clamping means for fixing in place measuring means in said second slot.

3. The invention as set forth in claim 2 wherein at least one of said second top apertures and its associated second vertical passageway and second bottom aperture are adapted to receive a knife edge.

4. The invention as set forth in claim 2 wherein at least one of said second top apertures, its communicat-;

ing second vertical passageway, and second bottom aperture are adapted to receive a conventional fountain pen, said second vertical passageway tapering to the dimensions of a conventional fountain pen point at said second bottom aperture to expose only said fountain pen point to contact with objects outside the drawing instrument.

5. The invention as set forth in claim 2 wherein first and second springs communicating with said first and second slots, respectively, are adapted to urge measuring means in said slots in a substantially transverse direction to that of said slots and in a plane substantially parallel to them so as to align said measuring means within said sliding holder and said drawing instrument, respectively, and wherein a multiplicity of zero point indicating lines are disposed on said top surface of said drawing instrument body and directed substantially perpendicularly to the direction of said second slot, one of said zero point indicating lines passing through the center of each one of said second top apertures and corresponding to the related index line of said second top apertures.

6. A sliding compass for adjustably describing an. arc

of a selected radius length comprising:

a sliding holder and a drawing instrument adapted. to be connected by a measuring means, said sliding holder having; r i

a body with first top and bottom surfaces and first front and back longitudinal ends; a first slot with a first front aperture at said first front longitudinal end for receiving measuring.

means extending longitudinally along the length of said sliding holder body and terminating in a back aperture at said first back longitudinal end;

at least one index line disposed on said topsurface of said sliding holder body and directed substantially perpendicularly to the direction of said first slot;

a first top aperture in said top surfacefor receiving a pivot pin, said top aperture communicating with a. first vertical passageway extending I between said top and bottom surfaces of said sliding holder body in a substantially perpendicular direction tothe plane of said first slot, said first vertical passageway terminating, in a bottom aperture, the center of said topaper:

ture lyin along said index, line closest to the front aperture of said first. slot;

a first adjustable clamping .means for fixing in place measuring means in said first slot;

a first narrow channel for receiving narrow measuring means said first narrow channel extending longitudinally substantially parallel to said first slot through said sliding holder body and terminating in apertures at said front and back longitudinal ends of-said sliding holder body;

said sliding holder body having a transparent portion for facilitating visual alignment of a measuring mark on said measuring means with a selected index line;

and said drawing instrument having a body .with second top and bottom surfaces and a second front longitudinal end;

a second slot with a second front aperture at said second front longitudinal end for receiving measuring means, said second slot extending longitudinally through said drawing instrument body and ending within said drawing instrument body at a first planar end surface at least one second top aperture in said top surface communicating with a second vertical passageway directed substantially perpendicularly to the plane of said second slot and extending between said top and bottom surfaces in said drawing instrument body, said second vertical passageway terminating at a second bottom aperture in said bottom surface, said second top aperture, second vertical passageway, and second bottom aperture being adapted to receive are describing means, the center of said second top aperture closest to said second slot front aperture being substantially in the same plane as said planar end surface;

a second adjustable clamping means for fixing in place measuring means in said second slot;

and a second narrow channel for receiving narrow measuring means, said second narow channel extending longitudinally through said drawing instrument body substantially parallel to said ,second slot andyterminating in an aperture, at said front longitudinal end of .said drawing in strument body and at a second planar end surfaceplane is substantially parallel to that of said first planar end surface and spaced longitudinally from the plane of said first planar end surface to provide room between said planar surfaces to accommodate ahook assem- 7 My of a conventional tape measure.

. 7. The invention as set forth inclaim 6 wherein a longitudinal extension of said sliding holder is provided to serve as a rest space for a spool of conventional tape measure and wherein a third bottom aperture disposed within said drawing instrument body, adjacent said second planar end surface and communicating with said secondslot is adapted to receive ahook assembly of a conventional tape meausre.

References Cited UNITED STATES PATENTS 1,572,237 I 2/1926 Hunt. 2,443,672 6/ 1948 Allen. 2,581,858 1/1952 Hilt et a1. 2,752,683 7/1956 Crane. 3,081,545 3/1963 Bergman.

812,322 2/1906 Badger 33-158 1,500,623 7/1924 Hurd 33-158 1,988,095 l/1935 Stockman.

2,176,681 10/1939 Paege 33-158 2,542,561 2/ 1951 Olejniczak. 2,681,507 6/ 1954 Underwood.

' FOREIGN PATENTS 290,500 3/1916 Germany.

604,777 10/1934 Germany.

HARRY N, HAROIAN, Primary Examiner Us. c1. X.R. 33-138 2 5 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,5O9 63l Dated May 5 1970 Inventofls) Eiii Shimoyama It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3 line 68 for "9" read --9 Column 4 line 17, for "6-2 and 6-1" read --6-2 and 5-1--. Column 7 line 23, after "surface" insert a semicolon; line 41, for 'narow" read Column 8 line 5, before "plane" insert -whose--.

' narrow- SIGNED MEL) SEALFD Ms 251970 we (SEAL) Afloat:

wmrm x mm n: 9" JR.

Offim v Commissioner of Patents 

